The nest of the shag is continually added to by the male, not only while the eggs are in process of incubation, but after they are hatched, and when the young are being brought up. In a sense, therefore, it may be said to be never finished, though for all practical purposes it is so before the female bird begins to sit. That up to this period the female as well as the male bird takes part in the building of the nest I cannot but think, but from the time of my arrival on the island I never saw the two either diving for or carrying seaweed together. Once I saw a pair of birds together high up on the cliffs, where some tufts of grass grew in the niches. One of these birds only pulled out some of the grass, and flew away with it, accompanied by the other. It is not only seaweed that is used by these birds in the construction of the nest. In many that I saw grass alone was visible, though I have no doubt seaweed was underneath it; and one in particular had quite an ornamental appearance, from being covered all over with some land plant having a number of small blue flowers; and this I have observed in other nests, though not to the same extent. I think it was on this same nest that I noticed the picked and partially bleached skeleton—with the head and wings still feathered—of a puffin. It had, to be sure, a sorry appearance to the human—at least to the civilized human—eye, but if it had not been brought there for the sake of ornament, I can think of no other reason; and brought there or at least placed upon the nest by the bird it must almost certainly have been. The brilliant beak and saliently-marked head of the puffin must be here remembered. Again, fair-sized pieces of wood or spar, cast up by the sea and whitened by it, are often to be seen stuck amongst the seaweed, and on one occasion I saw a bird fly with one of these to its nest and place it upon it. In all this, as it seems to me, the beginnings of a tendency to ornament the nest are clearly exhibited.